Easy data structure and algorithm practice puzzle.
Given the lines of a poem, return the first letter of each line, uppercased and joined together. So hope, everyone, loves, love, obviously spells "HELLO". Walk the lines once, grab each first letter, uppercase it, and add it to the result.
Solve it three ways: snap the jigsaw pieces together, fill in the blanks, or type it from scratch against the tests. This one is free.
Every line of the solution comes with a note explaining why it is there, and a step by step replay shows the code running. At level 3, where you type it yourself, you can ask for an AI mock interview on this problem that ends with a hiring manager's scorecard.
Then grow it into a real project with the Software Engineer button: this puzzle becomes the Track Fuzzy Matcher, a pipeline you can run and download. See every Software Engineer project.
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